Hæmocytometer.



M. LEVY.

HAEMOCYTOMETER.

.APPLICATION man sEPT.3o.\s1a,

1,21 4,'33 1 Pauted Jan. 30, 1917 if? Sq. mm.

j mm). Zeep j@ Jg. mm.,

@Nutmeg MAX LEVY, OF

PHILADELPHIA, PENNSYLVANIA.

l HEMOCYTOMETER.

Specification of Letters Patent. y

Patented Jan. 30, 1917.

Application ledSepte-mber 30, 1916. Serial No. 128,200.

To all whom t may concern:

Be it known that I, MAX LEVY; a. citizen of the United States of America., residing at Philadelphia, in the county of Philadelphia and Stute of Pennsylvanie, have invented certain hcw and useful Improvements in Hmocytometers, of which the following is n specification.

` This invention relates to haemocytometers the object of my'improvements being to provide such a. device with e counting cell oi chamber that is of greater average accuracy, us to the depth thereof and-to obviete to a greetextent or Wholly-the liability of separation of the seele member from its buse, und to provide a construction in which the cover-plete Will be-supported by 'the slide or base. In. other words it may be mid that the purposeof this invention is to provide a. hlnocytmeter with e. counting cell or chumber'which will be positioned at a. denite distux1ce.l3elow the surface of fthe-.glass slide or base in'dlhin which the cover-plate will be supported directly by the slide or base. 'In the priornrtlimocytometers ihave Vbeen 'constructed .in such amnner tliut the glass slide orbase has aittached thereto rests or supports for the cover plate which rests or supports are ce mented tofthe surface of the slide or base,

nndobetween these rests or supports the cell or scale slip is cemented, in which construction the bottom of the gutter or l tters is I' formed by the face of 'the slide or ase, and

obviously the cell or scle slip and the sup'- port or supports for the cover-plate extend above the plane-of the face .of the slide or buse'l and euch4 piece is heldl in place by cement. -Writh this form ofconstruction the cell or scale slip muy be provided with two counting' scales." Another well known form of hmocytoineter that has a. `single cell or counting chamber comprises u base or slide upon which is mounted or attached by cecovenplnterests upon thefipntured;equal-efV und: provides ucounting' chamber uboveath'e i Idisk #that'has p construction 'whichincludesA ment. a lsquareof glass havingtherethrough a circu aropehing and witinl-,thisvppening is'vlocted e` smaller f'circulzi'r'-dsk "thzit 'lisis thereon: the net orV Searle,- this circuler dislcis nlso cemented tothebuseor slide sind. is surrounded by continuous gutter. `In use the thereonV the ntfor scale. p A u vplurality of parts' which are connected to` the base or slide by'cement involvese method of lconthe surface bf or recesses Y,

except a's'l'to cost,

or scales 9, 9,the

struction that' includes are detrimental to the accuracy of the device nnd ,the resulting structure is one in which the cover-plute support or supports and the net or seele slip or disk are above the plane 'of the bese or slide. i A characteristic of zuhzemocytometer made to accord with my invention and by which I secure grent'ereccln-ecy as to' the zwei-age depth of the cell chamber., and practically eliminute liability of separation of the parts, resides in using the plaine face of the buse or slide es the support for the cover plate und in positioning the cell chamber below the pla-ne of the face of the base or slide,

In the aecomj'ienying f lrawinffe is u plan view of e, hemocytometer mudo to accord with my invention, the sume hzrvllig a. single net or seule., Fig. Qlis a plan view of a modiction, in which the buse orslide is provided With two nets or scales. Fig. 3

sectionl showing one form is :t longitudinal l of Vmy improvement. Fig. e is n lol'lg'itudinal Fig; l. Fig. 5 is several factors Whicllp section on theline A1--Ll of a longitudinul section on the line 2--2I of Fig.V 2,V and Fig. 6 is e` sectional view of :i modification.

Referring primarily to Figs. 3, l and 5 of the drawings, the buse or slide 6 is somewhat thicker than the plete usually selected for slides used for the sume purpose, so that the average thickness of the slide will be the sume; :is the usual thickness of heemocytomf' "eters nsl heretoforeconstructed, und in such n plut-ethere nre formed transverse grooves vslide'betweemthe grooves or recesses being reduced in thickness; such portion 8 having etched or ruled thereon u microscopicnet or' sculev9 which with the cever-plete10v constitutes thexcounting chamber. p

The embodiment of my invention in a form wherein the net or scale is formed Vupon unintegral part of the plate is ideal of manufacture, und l when desired :tpiovide the'device with two nets l counting chambers of the slide will behsepurated ce'ntrzlllyby n groove for recess .11".

7, the portionof Athe plete or los v In constructing n hesmocytozneter in which with: the buse or .slide the glass plete has denth to rovidc utters or rrcuifhs which K l V L e thesenle or net slip or pert 8 is notintegrnl groove orrece is provided with a recess'12 to receive a net or scale s1 1p.8, upon which is ruled'the scale 9. AThe recess 12 and the 5 slip 8` are of practically the same width .and the slip is he vide the correct' de th belovv` thelplane'.-sur-v face ofthe base an ,slide.-

The 'thickness of the slip 8 upon which is ruled the net orscale 9, and the-cement de termines the depth of the'cell'or counting chamber.' The side Walls of-the recess12 be- 1 tween which the slip 8 is located n 'ot only Lcorrectly positions the slip but also affords protection for the cement against the fiuids employed in counting, cleansing and sterilizing thehaemocytometer'.

It will be particularly noted that the slide orbase' is transversely grooved or recessed or'its full Widthf-to a depth sufficient to provide for the depth of the counting chamber' the slip of glass on which the rnet or scae is -ruled, and a lm of transparent cement, so that Vin assemblingpressure appliedl to. the vscaleslip will ldetermine the depth of 'the counting chamber accurately,l

irrespective of any inequality asvto `the'depth of' the recess or thickness of the scale-slip.

Inthe form or ty e" of hzemocytomet'ers shown by Fig. 6.0i t edrawings the scale,- slip is of the full Width of Va transverse recess formed in the slide and is cemented to the face of the'r'ecess, and -in this modification the gutters are formed by ting away a portion of the scale-slip;

A. haemocytometer as herein set forth provides a counting chamber which isbelow o the surface of the face of the slide and said counting chamber and the transverse gutters or grooves are in use both bridged by` the cover-plate which rests upon the face of the slide and owing tov'the lateral c'on- 4 5 tinuity of tl ie counting chamber the capillary action after the cover-plate is put-fon is uniform-and' results in an even distribution ofthe fcorpuscles over the counting chamber.

1. A haemocytometer having its counting 4chamber positioned below the face of the slide,rfor use witlra cover-plate that is sup-l ported by the lslide to bridge the counting chamber.

. 2. A hsemocytome'ter comprising .a glass slide having a counting-chamber? positioned d in-place by"l ay film of cement of such character that a portionI thereof-mayv be removed by pressure upon the sliptopr" lowering or cutf Abelow the plane ofthe face of the slide, re Y.cesses in the slide located alongsideof the counting chamber and av cover-plate ada ted to rest pon the face of the slide to bridge the counting chamber and the recesses.

3. A haemocytomet'er comprising a slide in- 'which is formed a transverse recess, a scaleslip cemented in the recess and maintained so that .the face of the scale-slip will be be low the plane of the face of. the slide and a' cover plate which is supported by direct engagement with the face of the slide to pro-1 vide above the scale-slip a counting chamber.

4; A haemocytometer comprisinga slide in which is formed a recess, a scale-slip'of less thickness than the depth ofthe recess which is cemented to the slideand maintained so that the face of the scale-slip -Will be below the plane of the face of the'slide and a cover which is supported by direct engagement y with the face ofthe slide beyond the recess to provide above the scale-slip a counting chamber. l

5. A haemocytometer comprising a slidein which is formed a `transverse recess and a scale-slip receivin" recess, a scale-slip cemented in the sca e-slip receiving recess so that the face of the scale-slip will be maintained below "the 'plane of the face of the slide, for use with a'coV'er-plate that is supported by the facegf the slide to bridgev the scale-slipv and the grooves'adjacent to the \sides of the scale-slip. i

l (i. hzemocytometer comprising a glass slide in which is formed a transverse recess and a deeper centrally located scale-slip receiifing recess, a scale-slip maintained in the` scale-slip receiving recess by. cement, the" quantity of cement and the thickness .of the 95.

scale-slip being such as. to positionthe face of the scale-slip below the planel of the face of the Slide to provide with a cover-plate that is maintained directly upon the face of the slide a counting chamber.

` 7. A- haelnocytometer comprising a' glass slide in which is 'formed a recess, a glass scale-slip providedcn its surface with a ruled scale,.. a film of cement for maintain, ingthe se'aleslip in place the combined thickness of thelscale-slip and the lilrn of cement-being such as to position the. scale-slip 'below the face of theo'slide "to provide acounting chamber, and gutters oneach side of the counting chamber.

' fmXLEvY. 

